Pneumatic tire for vehicles.



I. S. MGGIEHAN.

PNEUMATIC TIRE FOR VEHICLES. APPLICATION FILED MAY 15,1911.

1, 1 1 0,451, Patented Sept. 15, 1914.

WWII/E8858:

541; AP. 4am

ISAAC. s. MoGIEI-IAN, or LdNDbN, ENGLAND.

PNEUMATIC TIRE FOR\'V-EHICLES.

Specification of Letters Patent.

. Patented Sept. 15, 1914.

Application filed. May 15, 1911. Serial No. 627,315.

T0 all'wlwm it may concern I Be it known that I, ISAAC SEAMAN Mc-GIEHAN, a citizen of the United States, and, a resident of 11 Regentstreet, Londong S. England, have invented a new and; useful Improvementin Pneumatic Tires forj Vehicles, of which the following is a speci-;fication. t

This invention relates to the constructionE and reconstruction ofpneumatic tires for; vehicles. i

It has for its object to create a tire con-t structed wholly of rubberfilled fabric, the; inner carcass of which can be made and vulcanizedseparately from the tread portion,; and reinforced and strengthened bythe ad, dition of the tread portion which may also} be vulcanizedseparately, so that the tire may be built up by the wrapping process idesired. The tread is so formed and com-' pressed before it applicationto the carcass that it becomes non-stretchable, and the tire is verymuch stronger and more durable than those of the usual method ofconstruction, and creates a more homogeneous structure. The carcass andtread can be of one single structure, if desired, and vulcanized assuch.

In the accompanying drawings, which form a part of this specification,my invention is illustrated in various figures with similar letters ofreference to indicate corresponding parts.

Figure 1 represents the tire complete, with the carcass a. which formsthe foundation, and the tread or wear-surface a. made together,-theconstruction of which will be hereinafter described. Fig. 2 representsthe carcass a. as it is sometimes molded and vul canized before thetread 0. is applied. Fig. 3 represents the tread after it is completedand vulcanized'before it is applied to the carcass. In this form it canbe used for new tires or for reconstructing old carcasses.

)pen mesh fabricis used in order that the thin spreading rubber, whencoming in contact with the fabric, practically surrounds each strandindependently, thus each is better filled with rubber, the capillaryattraction of the strand taking in rubber from all sides except where itcrosses 1ts neighbor.

One of the prlncipal objects in having the .mesh particularly open isthat a greater amount of rubber may be filled into the mesh of thefabric. Thus when built up, the rubber joins'and unites with that partofthe rubber which fills the mesh in the next layer of fabric, and so onthrough the whole' thickness of the carcass or tread, forming smallsquare irregular columns of rubber which provide a holding and wearingsurface that cannot be ripped, torn, blistered or str pped, orseparated.

The method of constructing the tread separately is to take sheets offabric the desired sizes and thicknesses, with a very open mesh,

. say eight or ten to the inch, and spread or friction them with rubberto the extent that the open spaces between the strands of fabric arefilled with rubber in the form of square blocks, leaving as little as:possible on the surface. "The sheets are then cut on the bias inlengths and widths suitable to form a tread band of the desired size tofit f' the carcass, as illustrated in Fig. 3 in cross sections. Thesestrips graduate in width from 6. to 6 .tl1e outer strip e beingsufficiently broad to form a transverse circle over the carcass a. fromb. to b. Fig. l. The narrow strip 6. being next to the center of thecarcass, the whole tread taking the shape of a crescent as Fig. 3, withthe narrowest piece of fabric 6. forming the inside center of thecrescent, and vulcanized on a circular mandrel in this form,the treadforming an endless non-stretchable band.

The crescent tread thus provided is made a fraction smaller than thecircumference of the carcass to which it is to be applied, and it alsoforms a sharper transverse curvature than the carcass. Thus, when it isvulcanized to the carcass as hereinafter described, it imparts asphincter grip which draws against the carcass and strengthens the unionbetween the two. The fabric tread in this way reinforces andstrengthensthe carcass;

the sharper transverse curvature causes the sides of the crescent to laycloser against the wall of the carcass, and prevents separation at thatpoint.

In reconstructing old covers with this principle, the old or worn coveris placed upon a revolving mandrel, and the 'old rub-' her is cut,scraped and buffed from the original carcass until the original fabricfoundation is reached. The surface is then solutioned and covered with-a sheet .of quick-curing rubber. Theunder side ofthe finished treadband, as in Fig. 3 is also coated with the same solution. The tread isthen put in place on the old .carcass, and.

thetwo are bound tightly with strips or bands of canvas which have beensoaked in boiling water or a steam chest. The winding is done verytightly to make a very close union between the casing and the new tread,and' is continued until the entire tire is covered. After this is done,the tire so wound, is placed in a vulcanizer and remains there until therubber which unites the cover and casing is thoroughly cured andvulcanized. The canvas is then unwound, and the process ofreconstruction is complete.

The method of applyingthe tread band to a new carcass is the same asthat above described. I

In making new tires complete as one structure, the carcass a, is usuallybegun with a very tough fabric with a sufficient number of layers tocreate the body or carcass I proper, the number of body layers dependmgto a great extent upon the size of the tire. The carcass being providedwith sustaining beads of any desired form. The process of building up.is continued preferably with open mesh fabric as above described. Thetread 0, being built on the carcass in the same manner as previouslydeof different widths formed into a crescent band united thereto by aninterposed film of softer rubber, all homogeneously vulcanizedsubstantially as described.

2. A reconstructed pneumatic tire consisting of a suitable carcass orfoundation in combination with a substantially non-stretchable fabricband tread portion united to the said carcass by means of anintermediate film of quick-curing rubber as herein specified.

ISAAC S. MoGIEHAN. Witnesses c.- P. LiDDON; R. .WILLIAMB.

